zeroberts Posted January 10, 2011 Posted January 10, 2011 So I've been building some small aerial shells, and doing pretty well with it too I think. I've been using firefly and tigertail based stars for these, but I want to expand into the use of colors. I've been reading up and I'm wondering if the presence or absence of red gum will affect my color saturation in the flame. I read that the substitution of red gum with other fuel/binders will adversely affect coloration. This leads me to assume that its altogether absence would rather negatively affect my color saturation. I've made it this far without red gum and I've done very well so far without it. I ordered some to use in my stars, but what I really need to know is if the addition of red gum to my star compositions will help me with my pale ugly flame issue that I've been having.
50AE Posted January 10, 2011 Posted January 10, 2011 You can't remove red gum from a star composition. At least, you have to substitute it with another fuel. Red gum is a fast burning fuel. Depending of the composition, you can substitute it. As far as I know, it can be replaces by shellac in 1:1 ratio. Shellac is almost two times slower burning than red gum, so testing should be done. Why don't you post the compositions you've liked and we can discuss them here.
zeroberts Posted January 11, 2011 Author Posted January 11, 2011 This first one I found in these forums and did try: KP: 66.1CuO: 13.2Parlon: 10.7Red Gum: 9.8Dextrin: 5 However the comp I made was sans the red gum because I dont have any in my chem inventory. It burned blue in tests, but very pale. The flame does appear mildly improved after the mix has been wetted and pumped into stars, but not a wowing blue like the videos posted with the formula depict. I found another composition with, dare I use the pun... glowing reviews (forgive me), it is as follows: Potassium Chlorate: 66.5Red Gum: 9.9CuO: 13.4Parlon: 5.4Dextrin: 4.8 I've not tried this one yet. I figured I'd wait till my red gum comes in tomorrow or wednesday before giving it a real go, plus I do have a concern about this formula. I noted that the parlon concentration is much much lower in this composition than that of the chlorine donor in any other composition I've seen in my readings. I feel like I understand just about every other principal of pyrotechnics I've been employing, but I'm very very new to color chemistry (as in just began this endeavor two days ago) so all the explanation and advice I can get would be very much appreciated. Thanks!
Peret Posted January 11, 2011 Posted January 11, 2011 I noted that the parlon concentration is much much lower in this composition than that of the chlorine donor in any other composition I've seen in my readings. That's because the potassium chlorate in this formula is a better chlorine donor than the perchlorate in the other comps. Not many people use chlorate stars these days because of the sensitivity, especially around sulfur (or black powder). I think you would be safer staying away from it until you get a bit more experienced. You can make any and every color with perchlorates (K or A). There are a couple of cases where chlorates are required to get the ultimate purity and depth of color, but they're not beginners projects. Barium chlorate green stars have been known to ignite if you step on them.
petroleum Posted January 11, 2011 Posted January 11, 2011 About Red Gum substitution: I have tried to substitute Red Gum with Novolack resin in colored star formulas with known success. In my conditions there was no color changes. Burning rate also was the same as with Red Gum. In all cases the hardeness of the stars with Novolack resin was much better, than with Red Gum. But it must be considered, that Novolack resin can contain some % of pure phenol.
dave321 Posted January 11, 2011 Posted January 11, 2011 About Red Gum substitution: I have tried to substitute Red Gum with Novolack resin in colored star formulas with known success. In my conditions there was no color changes. Burning rate also was the same as with Red Gum. In all cases the hardeness of the stars with Novolack resin was much better, than with Red Gum. But it must be considered, that Novolack resin can contain some % of pure phenol. hi, what is novalc resin ? do you have a brand mane for the product and where did you get it ?i want to see if it is available in the uk dave321
WSM Posted January 12, 2011 Posted January 12, 2011 When testing blue stars, try to be at a distance from them. Even really good blues look pale or washed out, up close. I had to learn this lesson the hard way many years ago. Have fun, be safe and tell us about it. WSM
zeroberts Posted January 12, 2011 Author Posted January 12, 2011 Oops, typo in the second comp I listed. I double checked, and the formula I read calls for potassium PERchlorate. Thats why I noted the low parlon concentration as unusual. And as for working with chlorates, thats not terribly new territory for me. I've used potassium chlorate in a few other compositions, including a small variety of flash, and of course my long and ongoing love affair with H3 haha. I'm fairly proficient with other pyro principles, sciences, and certainly safety procedures. Its just color chemistry that I'm starting fresh into. I also feel like I need a more concrete answer. Will the addition of the missing red gum improve my color saturation? My color is apparent, I would even call it decent. But a couple shades deeper would make me a very happy man. Thank you for your posts, help, and support.
Peret Posted January 12, 2011 Posted January 12, 2011 And as for working with chlorates, thats not terribly new territory for me. I've used potassium chlorate in a few other compositions, including a small variety of flash, and of course my long and ongoing love affair with H3 haha. I'm fairly proficient with other pyro principles, sciences, and certainly safety procedures. Its just color chemistry that I'm starting fresh into. I'm sorry for making assumptions then. It's a standard reaction to people with a low post count. Nothing beats a barium chlorate green (barium chlorate 9, red gum 1) for color and saturation, there is no substitute, but it's too sensitive for my taste. I won't store this composition and I'm careful handling the stars.
petroleum Posted January 12, 2011 Posted January 12, 2011 hi, what is novalc resin ? do you have a brand mane for the product and where did you get it ?i want to see if it is available in the uk dave321 Hi!Novolac resin it is type of phenol-formaldehyde resin.I dont know, where can You get this product in UK, but in Europe You can buy it there http://www.pyro-stuff.com/store/phenolic-resin-p-120.html .I bought it from one Estonian stock (product age is about 25 years, it was made in USSR. Brand name was: смолa СФ-0112 (идитол)).
zeroberts Posted January 20, 2011 Author Posted January 20, 2011 ok ok so after doing some reading around I think I've discovered the root of my problem. I have anti-cake KClO4. I've read around and I've gotten from multiple sources that impurities, even some rather minor impurities can potentially cause severe color deficiency. I've done everything precisely according to formula and procedure and have come up with consistently deficient results. My last conclusion is that the anti-cake (cab-o-sil I'm sure) is the damaging agent. I've ordered technical grade KClO4 instead of the anti-cake stuff. If this doesnt work I'm just gonna turn my entire workshop over to the haz mat disposal crew and start making jewelry or something. Because seriously. This is getting a little silly.
Mumbles Posted January 20, 2011 Posted January 20, 2011 I really doubt it is the anti-cake. Cab-o-sil really doesn't impart any color into the flame, and is present in extremely low amounts. It's anticake like tricalcium phosphate, and a sodium one, that are the ones that really cause the problems with colors. I wouldn't give up until you try the formula as given. Leaving out 10% of a formula is going to drastically change it's function and presentation. Consider leaving out all the sulfur in black powder without replacing it with anything else. It would probably smoulder at best. Colored stars are fairly sensitive to composition balance. Too much fuel, or too much oxidizer can give very poor effects. As WSM mentioned, you also don't want to look directly at the star. This brings be to point #2, make sure you're testing these as stars. The composition doesn't preform the same as a powder. You want to look at the light reflected off a piece of paper tacked to a tree or wall or something. It will more accurately depict the flame color when viewed from a distance. When you're too close the light over powers your retinas and everything appears washed out.
zeroberts Posted January 21, 2011 Author Posted January 21, 2011 I really doubt it is the anti-cake. Cab-o-sil really doesn't impart any color into the flame, and is present in extremely low amounts. It's anticake like tricalcium phosphate, and a sodium one, that are the ones that really cause the problems with colors. I wouldn't give up until you try the formula as given. Leaving out 10% of a formula is going to drastically change it's function and presentation. Consider leaving out all the sulfur in black powder without replacing it with anything else. It would probably smoulder at best. Colored stars are fairly sensitive to composition balance. Too much fuel, or too much oxidizer can give very poor effects. As WSM mentioned, you also don't want to look directly at the star. This brings be to point #2, make sure you're testing these as stars. The composition doesn't preform the same as a powder. You want to look at the light reflected off a piece of paper tacked to a tree or wall or something. It will more accurately depict the flame color when viewed from a distance. When you're too close the light over powers your retinas and everything appears washed out. My tech grade KClO4 is in so I'll be in the lab tonight. I have produced several compositions in precise following of the formulas provided, no substitutions, and still insufficient results. This is why I lastly accuse the anti-cake. But the jury is out till tonights batch of blue dries. As I started my testing, testing and retesting I did notice the difference in performance between powdered comp and properly manufactured stars. A fascinating behavior I think. And I get good perspective of ambient color of the star this time of year. Everything is white with snow so a single star lights up the whole neighborhood. But in a less snowy season I'll use that paper trick, thats pretty keen. I test my stars in small mines (one to three star shot), this gives good perspective of how the star behaves in flight, and all behaviors of the star and its burning seem more ideal in flight anyway. Color chemistry is an interesting new adventure for me. It makes me appreciate the ease of BP type stars. I really need to start posting pictures and videos.... anywho, I'll post again with results after seeing the performance of my stars made with the tech grade KClO4.
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